Combine milk chocolate, condensed milk, and butter in a double boiler over simmering water, stirring frequently and scraping down the sides with a rubber spatula, until chocolate is melted, about 5 minutes. Remove from heat.
Mix almonds and coconut into melted chocolate. Pour into a 9-inch pan and spread evenly. Pat down to make fudge even. Refrigerate until firm, about 1 hour. Cut into squares.